U.S. patent number 11,253,470 [Application Number 16/474,883] was granted by the patent office on 2022-02-22 for composition for external application.
This patent grant is currently assigned to Kobayashi Pharmaceutical Co., Ltd.. The grantee listed for this patent is Kobayashi Pharmaceutical Co., Ltd.. Invention is credited to Junji Akaki, Masahiro Goto, Takahiro Nakata.
United States Patent |
11,253,470 |
Nakata , et al. |
February 22, 2022 |
Composition for external application
Abstract
An object of the present invention is to provide a composition
for external use having excellent percutaneous absorption
properties. A composition for external use comprising a
water-soluble fraction dispersed in an oily phase, wherein the
water-soluble fraction contains a surfactant and a solution in
which a water-soluble substance is dissolved in water, and the
content of the water in the water-soluble fraction is 0.1 to 2.5%
by weight based on the composition for external use.
Inventors: |
Nakata; Takahiro (Ibaraki,
JP), Akaki; Junji (Ibaraki, JP), Goto;
Masahiro (Fukuoka, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Kobayashi Pharmaceutical Co., Ltd. |
Osaka |
N/A |
JP |
|
|
Assignee: |
Kobayashi Pharmaceutical Co.,
Ltd. (Osaka, JP)
|
Family
ID: |
62709364 |
Appl.
No.: |
16/474,883 |
Filed: |
December 26, 2017 |
PCT
Filed: |
December 26, 2017 |
PCT No.: |
PCT/JP2017/046586 |
371(c)(1),(2),(4) Date: |
June 28, 2019 |
PCT
Pub. No.: |
WO2018/124043 |
PCT
Pub. Date: |
July 05, 2018 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190336438 A1 |
Nov 7, 2019 |
|
Foreign Application Priority Data
|
|
|
|
|
Dec 28, 2016 [JP] |
|
|
JP2016-257056 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K
47/06 (20130101); A61K 8/06 (20130101); A61K
8/37 (20130101); A61K 47/26 (20130101); A61K
8/64 (20130101); A61K 47/14 (20130101); A61K
8/86 (20130101); A61K 8/60 (20130101); A61Q
19/00 (20130101); A61K 8/375 (20130101); A61K
9/107 (20130101); A61K 31/715 (20130101); A61K
9/0014 (20130101); A61K 8/73 (20130101); A61K
47/44 (20130101) |
Current International
Class: |
A61K
9/00 (20060101); A61K 8/64 (20060101); A61K
8/73 (20060101); A61K 8/86 (20060101); A61K
9/107 (20060101); A61K 31/715 (20060101); A61K
47/14 (20170101); A61Q 19/00 (20060101); A61K
8/60 (20060101); A61K 8/37 (20060101); A61K
8/06 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
10-505865 |
|
Jun 1998 |
|
JP |
|
2011-037723 |
|
Feb 2011 |
|
JP |
|
2011-037723 |
|
Feb 2011 |
|
JP |
|
4843494 |
|
Dec 2011 |
|
JP |
|
WO 96/24325 |
|
Aug 1996 |
|
WO |
|
WO 2006/025583 |
|
Mar 2006 |
|
WO |
|
WO 2007/070983 |
|
Jun 2007 |
|
WO |
|
Other References
Shimadzu
(https://www.shimadzu.com/an/service-support/technical-support/an-
alysis-basics/basic/38/38lab.html; downloaded on Oct. 27, 2020).
cited by examiner .
Phosphoric acid density
(https://www.thomassci.com/Chemicals/Acids/_/Phosphoric-Acid-Purified?q=P-
hosphoric%20Acid%2085; downloaded on Oct. 27, 2020). cited by
examiner .
https://www.redlandcitybulletin.com.au/story/6689408/the-magic-healing-pow-
ers-of-aloe-vera-its-so-natural/ (downloaded on Mar. 31, 2021).
cited by examiner .
International Search Report for International Application No.
PCT/JP2017/046586, dated Mar. 20, 2018 (in 1 page). cited by
applicant .
Office Action in Chinese Patent Application No. 201780079048.8
dated Mar. 23, 2021. cited by applicant.
|
Primary Examiner: Bakshi; Pancham
Attorney, Agent or Firm: Knobbe, Martens, Olson & Bear,
LLP
Claims
The invention claimed is:
1. A composition for external use comprising a water-soluble
fraction dispersed in an oily phase, wherein: the water-soluble
fraction contains a surfactant and a solution in which a water
soluble substance is dissolved in water, the water soluble
substance is at least one selected from the group consisting of a
protein and a polysaccharide, and the content of the water in the
water-soluble fraction is 0.1 to 2.5% by weight of the total
composition for external use.
2. The composition for external use according to claim 1, wherein
the surfactant is a nonionic surfactant.
3. The composition for external use according to claim 1, wherein
the surfactant is at least one selected from the group consisting
of polyglycerin fatty acid esters, glycerin fatty acid esters,
sorbitan fatty acid esters, polyoxyethylene hydrogenated castor
oil, and sucrose fatty acid esters.
4. The composition for external use according to claim 1, wherein
the content of the surfactant is 0.1 to 20% by weight of the total
composition for external use.
5. The composition for external use according to claim 1, wherein
the content of the water-soluble substance is 0.0001 to 2.5% by
weight of the total composition for external use.
6. The composition for external use according to claim 5, wherein
the oily phase contains a liquid oil.
Description
TECHNICAL FIELD
The present invention relates to a composition for external use.
Specifically, the present invention relates to a composition for
external use having excellent percutaneous absorption
properties.
BACKGROUND ART
The horny layer of the skin, which is composed of oily substances
such as cholesterol and sphingolipids, is hydrophobic and dense,
and prevents evaporation of moisture from inside the body. On the
other hand, this structure of the horny layer becomes a barrier to
the penetration of medicines for external use into the skin. In
general, substances having molecular weights of more than about 500
are unlikely to penetrate into the skin. Because of this skin
barrier, percutaneous absorption of water-soluble substances has
been heretofore very difficult to achieve. Furthermore, dosage
forms of agents for external use containing water-soluble
substances are limited to lotions, gels, creams, and the like.
Thus, even if such an agent for external use is applied to the
skin, the water-soluble substance may be held in the water in the
formulation, and prevented from migrating into the skin. As a
result, the water-soluble substance is unlikely to be
percutaneously absorbed.
Various studies have been made regarding methods for improving the
percutaneous absorption properties of water-soluble substances.
Patent Literature 1, for example, discloses a composition for skin
that is suitable for percutaneous absorption, wherein a hydrophilic
segment is used as a core, the hydrophilic segment being produced
by mixing an oily phase containing an amphiphilic polymer in an
oily base and an aqueous phase containing a water-soluble drug in
an aqueous solvent, or by mixing an oily base and an aqueous phase
containing an amphiphilic polymer and a water-soluble drug in an
aqueous solvent; a hydrophobic segment is used as a shell; and the
composition comprises a polymer reversed micelle in which the
water-soluble drug is encapsulated.
Patent Literature 2, for example, discloses a S/O
(Solid-in-Oil)-type external preparation having excellent
percutaneous absorbability, comprising a medicine-containing
complex dissolved or dispersed in an oil phase, wherein the complex
contains a hydrophilic medicine covered with a surfactant, and is
solid.
These compositions for external use, however, are still
insufficient in terms of percutaneous absorption properties when
they contain a water-soluble substance, and have room for
improvement. Based on this prior art as a background, there is an
earnest desire for the development of a composition for external
use having excellent percutaneous absorption properties even when
the composition contains a water-soluble substance.
CITATION LIST
Patent Literature
Patent Literature 1: WO 2006/25583
Patent Literature 2: Japanese Patent No. 4,843,494
SUMMARY OF INVENTION
Technical Problem
An object of the present invention is to provide a composition for
external use containing a water-soluble substance and having
excellent percutaneous absorption properties.
Solution to Problem
The present inventors conducted extensive research to solve the
aforementioned problem, and found that a composition for external
use comprising a water-soluble fraction dispersed in an oily phase,
wherein the water-soluble fraction contains a surfactant and a
solution in which a water-soluble substance is dissolved in water,
and the content of the water in the water-soluble fraction is
within a specific range, can be provided as a composition for
external use having excellent percutaneous absorption properties.
The present inventors also found that the composition for external
use of the present invention has excellent percutaneous absorption
properties even when the composition contains a water-soluble
substance having a high molecular weight. The present invention has
been completed as a result of further study based on these
findings.
In summary, the present invention provides aspects of invention as
itemized below.
Item 1. A composition for external use comprising a water-soluble
fraction dispersed in an oily phase, wherein
the water-soluble fraction contains a surfactant and a solution in
which a water-soluble substance is dissolved in water, and
the content of the water in the water-soluble fraction is 0.1 to
2.5% by weight based on the composition for external use.
Item 2. The composition for external use according to item 1,
wherein the surfactant is a nonionic surfactant.
Item 3. The composition for external use according to item 1 or 2,
wherein the surfactant is at least one selected from the group
consisting of polyglycerin fatty acid esters, glycerin fatty acid
esters, sorbitan fatty acid esters, polyoxyethylene hydrogenated
castor oil, and sucrose fatty acid esters.
Item 4. The composition for external use according to any one of
items 1 to 3, wherein the content of the surfactant is 0.1 to 20%
by weight.
Item 5. The composition for external use according to any one of
items 1 to 4, wherein the water-soluble substance is one selected
from the group consisting of proteins and polysaccharides.
Item 6. The composition for external use according to any one of
items 1 to 5, wherein the content of the water-soluble substance is
0.0001 to 2.5% by weight.
Item 7. The composition for external use according to item 6,
wherein the oily phase contains a liquid oil.
Advantageous Effects of Invention
According to the present invention, there is provided a composition
for external use having excellent percutaneous absorption
properties. In particular, the composition for external use of the
present invention has excellent percutaneous absorption properties
even when it contains a water-soluble substance having a high
molecular weight, and thus, can be suitably used as carriers for
various drugs.
DESCRIPTION OF EMBODIMENTS
The composition for external use of the present invention is a
composition for external use comprising a water-soluble fraction
dispersed in an oily phase, wherein the water-soluble fraction
contains a surfactant and a solution in which a water-soluble
substance is dissolved in water, and the content of the water in
the water-soluble fraction is 0.1 to 2.5% by weight based on the
composition for external use. The composition for external use of
the present invention will be hereinafter described in detail.
Water-Soluble Fraction
In the present invention, the water-soluble fraction contains a
surfactant and a solution in which a water-soluble substance is
dissolved in water. The water-soluble fraction contains the
water-soluble substance, the water, and the surfactant as main
components. It is assumed that the water-soluble fraction is in the
state of a particle wherein the hydrophilic moiety of the
surfactant is associated with the solution in which the
water-soluble substance is dissolved in water, and coats the
surroundings of the solution, or, even if the coating is not
formed, the water-soluble fraction is dispersed in the oily phase.
Each of the components of the composition for external use of the
present invention will be described.
(Water-Soluble Substance)
The water-soluble substance to be used in the present invention is
not particularly limited as long as it exhibits water solubility,
and is pharmacologically or cosmetically acceptable; examples
include a water-soluble substance that dissolves in water
(20.degree. C.) at a ratio of 1 g or more of the water-soluble
substance to 100 g of the water, preferably 1 g or more of the
water-soluble substance to 30 g of the water, and more preferably 1
g or more of the water-soluble substance to 10 g of the water.
In the present invention, as the water-soluble substance, a
water-soluble substance is suitably used that exhibits
pharmacological or cosmetic efficacy, and is used as an active
ingredient for compositions for external use. This water-soluble
substance is not particularly limited in type, and may be any of a
low-molecular-weight substance having a molecular weight of less
than about 500 Da and a high-molecular-weight substance having a
molecular weight of about 500 Da or more.
Specific examples of the low-molecular-weight substance to be used
as the water-soluble substance include whitening agents, such as
L-ascorbic acid, sodium L-ascorbate, L-ascorbic acid monophosphate,
L-ascorbic acid-2-sulfate, L-ascorbic acid glucoside, arbutin,
kojic acid, kojic acid monobutyrate, kojic acid monocaprate, kojic
acid monopalmitate, kojic acid monostearate, kojic acid
monocinnamoate, kojic acid monobenzoate, kojic acid dibutyrate,
kojic acid dipalmitate, kojic acid distearate, kojic acid dioleate,
and tranexamic acid; antiinflammatory agents, such as dipotassium
glycyrrhizinate, ammonium glycyrrhizinate, glycyrrhetic acid,
allantoin, salicylic acid, glycol salicylate, methyl salicylate,
indomethacin, felbinac, diclofenac sodium, and loxoprofen sodium;
antihistamines, such as diphenhydramine hydrochloride and
chlorpheniramine maleate; local anesthetics, such as lidocaine,
dibucaine, procaine, tetracaine, bupivacaine, mepivacaine, and
chloroprocaine; bactericidal/antimicrobial agents, such as
benzalkonium chloride, dequalinium chloride, benzethonium chloride,
cetylpyridinium chloride, isopropylmethylphenol, chlorhexidine
hydrochloride, chlorhexidine gluconate, croconazole hydrochloride,
and zinc pyrithione; blood circulation promoters, such as nonanoic
acid vanillylamide, benzyl nicotinate, cepharanthine, and
carpronium chloride; antibiotics, such as tetracycline
hydrochloride; hormonal agents, such as oxytocin, corticotropin,
vasopressin, secretin, gastrin, and calcitonin; B vitamins and
derivatives thereof, such as vitamin B1, vitamin B2, niacin,
pantothenic acid, panthenol, vitamin B6, biotin, folic acid,
nicotinic acid, nicotinamide, and vitamin B.sub.12;
monosaccharides, such as glucosamine, N-acetyl glucosamine,
glucose, and fructose; disaccharides, such as maltose, sucrose,
lactose, and trehalose; oligosaccharides, such as
malto-oligosaccharides, galacto-oligosaccharides,
agaro-oligosaccharide, and xylo-oligosaccharides; and amino acids.
These low-molecular-weight compounds may be used alone or in
combinations of two or more.
Specific examples of the high-molecular-weight substance to be used
as the water-soluble substance include proteins, such as collagen,
cytokines, antibodies, vaccine antigens, albumin, and enzymes (such
as trypsin, lysozyme chloride, chymotrypsin, semi-alkaline
proteinase, serrapeptase, lipase, and hyaluronidase);
polysaccharides, such as heparinoids, hyaluronic acid, chondroitin
sulfate, chitosan, chitin, glycogen, carrageenan, fucoidan,
porphyran, xanthan gum, tuberose polysaccharides, quince seed
extract, gellan gum, alginic acid, pectin, carboxymethyl cellulose,
hydroxyethyl cellulose, hydroxypropyl cellulose, guar gum, agarose,
chitosan, pullulan, locust bean gum, galactan, gum arabic, tara
gum, tamarind seed gum, and salts thereof (such as alkali metal
salts, for example, sodium salt and potassium salt); and aloe
extract. These high-molecular-weight compounds may be used alone or
in combinations of two or more.
These water-soluble substances may be used alone or in combinations
of two or more.
With conventional percutaneous absorption technologies,
percutaneous absorption of water-soluble high-molecular-weight
substances, such as proteins and polysaccharides, has been very
difficult to achieve; however, with the composition for external
use of the present invention, even such water-soluble
high-molecular-weight substances can be effectively percutaneously
absorbed. In view of this effect of the present invention, the
water-soluble substance is preferably a water-soluble
high-molecular-weight substance, and more preferably a protein or a
polysaccharide, for example.
In the composition for external use of the present invention, the
water-soluble fraction contains the solution in which the
water-soluble substance is dissolved in water. The content of the
water-soluble substance in the solution contained in the
water-soluble fraction is, for example, 0.001 to 60% by weight,
preferably 0.001 to 50% by weight, more preferably 0.001 to 40% by
weight, still more preferably 1 to 40% by weight, and particularly
preferably 10 to 40% by weight.
The content of the water-soluble substance in the composition for
external use of the present invention may be appropriately set, in
accordance with the use of the composition for external use, the
type of the surfactant to be used, and the like; for example, the
content is 0.0001 to 2.5% by weight, preferably 0.0001 to 2% by
weight, and more preferably 0.0001 to 1.5% by weight.
(Surfactant)
The surfactant to be used in the present invention is not
particularly limited as long as it can achieve a water-in-oil-type
emulsion, and examples include known surfactants, such as nonionic
surfactants, anionic surfactants, cationic surfactants, and
amphoteric surfactants. Among the above, a nonionic surfactant is
preferred, in order to further improve the percutaneous absorption
properties of the composition for external use.
Examples of the nonionic surfactant that is typically used to form
the composition for external use of the present invention into a
water-in-oil type include polyglycerin fatty acid esters, glycerin
fatty acid esters, sorbitan fatty acid esters, propylene glycol
fatty acid esters, polyoxyethylene hydrogenated castor oil,
polyoxyethylene polyoxypropylene alkyl ethers, and sucrose fatty
acid esters.
A polyglycerin fatty acid ester is an ester of a fatty acid and
polyglycerin. In the polyglycerin fatty acid ester, the number of
ester bonds (the number of fatty acids attached to one molecule of
polyglycerin) is, for example, 1 to 10, preferably 1 to 6, and more
preferably 1 to 3. The number of carbon atoms in the fatty acid
constituting the polyglycerin fatty acid ester is, for example, 6
to 24, preferably 8 to 22, and more preferably 12 to 18.
Furthermore, the degree of polymerization of polyglycerin
constituting the polyglycerin fatty acid ester is, for example, 2
to 30, and preferably 2 to 10. Specific examples of the
polyglycerin fatty acid ester include polyglyceryl-2 stearate
(diglyceryl monostearate), polyglyceryl-2 oleate (diglyceryl
monooleate), polyglyceryl-4 oleate (tetraglyceryl monooleate),
polyglyceryl-10 oleate (decaglyceryl monooleate), polyglyceryl-10
trioleate (decaglyceryl trioleate), polyglyceryl-10 palmitate
(decaglyceryl monopalmitate), polyglyceryl-2 isostearate,
polyglyceryl-2 triisostearate, polyglyceryl-4 stearate,
polyglyceryl-6 tristearate, polyglyceryl-10 pentastearate,
polyglyceryl-10 pentahydroxystearate, polyglyceryl-10
pentaisostearate, polyglyceryl-10 pentaoleate, polyglyceryl-6
polyricinoleate, and polyglyceryl-10 polyricinoleate. Among these
polyglycerin fatty acid esters, for example, polyglyceryl-2
stearate, polyglyceryl-2 oleate, polyglyceryl-4 oleate,
polyglyceryl-10 oleate, polyglyceryl-10 trioleate, and
polyglyceryl-10 palmitate are preferred.
A glycerin fatty acid ester is a mono-, di-, or tri-ester of a
fatty acid and glycerin. The number of carbon atoms in the fatty
acid constituting the glycerin fatty acid ester is, for example, 6
to 24, preferably 8 to 22, and more preferably 12 to 18. Specific
examples of the glycerin fatty acid ester include glyceryl
monomyristate, glyceryl monostearate, glyceryl monoisostearate,
glyceryl monooleate, glyceryl dioleate, glyceryl trioleate, and
glyceryl distearate. Among these glycerin fatty acid esters, for
example, glyceryl monooleate, glyceryl distearate, and glyceryl
monomyristate are preferred.
A sorbitan fatty acid ester is a mono-, di-, or tri-ester of a
fatty acid and sorbitan. The number of carbon atoms in the fatty
acid constituting the sorbitan fatty acid ester is, for example, 6
to 24, preferably 8 to 22, and more preferably 12 to 18. Specific
examples of the sorbitan fatty acid ester include sorbitan
monostearate, sorbitan monoisostearate, sorbitan sesquiisostearate,
sorbitan sesquioleate, sorbitan monooleate, sorbitan trioleate,
sorbitan monopalmitate, and sorbitan monolaurate. Among these
sorbitan fatty acid esters, for example, sorbitan monooleate,
sorbitan trioleate, sorbitan monostearate, sorbitan monopalmitate,
and sorbitan monolaurate are preferred.
A propylene glycol fatty acid ester is a mono- or di-ester of a
fatty acid and propylene glycol. The number of carbon atoms in the
fatty acid constituting the propylene glycol fatty acid ester is,
for example, 6 to 24, preferably 8 to 22, and more preferably 12 to
18. Specific examples of the propylene glycol fatty acid ester
include propylene glycol monostearate, propylene glycol
monoisostearate, and propylene glycol monooleate.
Polyoxyethylene hydrogenated castor oil is a compound in which
hydrogenated castor oil has been etherified with a polyoxyethylene
chain. The addition molar number of ethylene oxide of the
polyoxyethylene chain in polyoxyethylene hydrogenated castor oil
is, for example, 5 to 100, preferably 10 to 80, and more preferably
20 to 60. Specific examples of polyoxyethylene hydrogenated castor
oil include PEG-5 hydrogenated castor oil, PEG-10 hydrogenated
castor oil, and PEG-60 hydrogenated castor oil (polyoxyethylene
hydrogenated castor oil 60). Among these types of polyoxyethylene
hydrogenated castor oil, PEG-60 hydrogenated castor oil, for
example, is preferred.
A polyoxyethylene polyoxypropylene alkyl ether is a compound in
which a polyoxyethylene polyoxypropylene chain is attached to an
alkyl group through an ether bond. Specific examples of the
polyoxyethylene polyoxypropylene alkyl ether include PPG-4
ceteth-1.
A sucrose fatty acid ester is an ester of a fatty acid and sucrose.
The number of carbon atoms in the fatty acid constituting the
sucrose fatty acid ester is, for example, 6 to 24, preferably 8 to
22, and more preferably 12 to 18. Specific examples of the sucrose
fatty acid ester include sucrose stearate, sucrose erucate, sucrose
laurate, sucrose behenate, sucrose palmitate, and sucrose oleate.
Among these sucrose fatty acid esters, sucrose erucate, for
example, is preferred.
From the viewpoint of further improving the percutaneous absorption
properties of the water-soluble substance, among these nonionic
surfactants, preferred are polyglycerin fatty acid esters, glycerin
fatty acid esters, sorbitan fatty acid esters, polyoxyethylene
hydrogenated castor oil, and sucrose fatty acid esters; more
preferred are polyglycerin fatty acid esters and glycerin fatty
acid esters; and particularly preferred are polyglycerin fatty acid
esters.
Among these nonionic surfactants, suitable specific examples
include polyglyceryl-2 stearate, polyglyceryl-2 oleate,
polyglyceryl-4 oleate, polyglyceryl-10 oleate, polyglyceryl-10
trioleate, polyglyceryl-10 palmitate, glyceryl monostearate,
glyceryl monooleate, glyceryl distearate, glyceryl monomyristate,
sorbitan monooleate, sorbitan trioleate, sorbitan monostearate,
sorbitan monopalmitate, sorbitan monolaurate, PEG-60 hydrogenated
castor oil, and sucrose erucate; more preferred are polyglyceryl-4
oleate, polyglyceryl-10 oleate, polyglyceryl-10 trioleate,
polyglyceryl-10 palmitate, glyceryl monooleate, sorbitan
monooleate, sorbitan trioleate, and sorbitan monolaurate; and
particularly preferred are polyglyceryl-4 oleate, polyglyceryl-10
oleate, polyglyceryl-10 trioleate, polyglyceryl-10 palmitate, and
glyceryl monooleate.
These nonionic surfactants may be used alone or in combinations of
two or more.
The content of the nonionic surfactant in the composition for
external use of the present invention may be appropriately set, in
accordance with the type of the surfactant to be used; for example,
the content is 0.1 to 20% by weight, preferably 0.5 to 10% by
weight, and more preferably 1.5 to 7.5% by weight.
(Aqueous-Phase Base)
The composition for external use of the present invention contains
water as an aqueous-phase base of the water-soluble fraction. In
the composition for external use of the present invention, the
content of the water in the water-soluble fraction is 0.1 to 2.5%
by weight based on the composition for external use. Because the
composition for external use of the present invention contains
water in a predetermined range of amounts, it has excellent
percutaneous absorption properties. The content of the water in the
water-soluble fraction is preferably 0.5 to 2% by weight, more
preferably 0.75 to 1.25% by weight, and still more preferably 0.75
to 1% by weight, for example, based on the composition for external
use, in order to further improve the percutaneous absorption
properties.
Oily Phase
Examples of an oily-phase base in the composition for external use
of the present invention include oily components, such as liquid
oils, solid oils, and higher alcohols.
A liquid oil is an oil that maintains a liquid form at 25.degree.
C. The liquid oil to be used in the present invention may be a
liquid oil that is generally used in cosmetic preparations,
pharmaceuticals for external use, and the like; examples include
vegetable oils, such as avocado oil, camellia oil, macadamia nut
oil, olive oil, almond oil, soybean oil, jojoba oil, cotton seed
oil, rapeseed oil, sesame oil, perilla oil, cinnamon oil, corn oil,
peanut oil, sunflower oil, cacao oil, mentha oil, bergamot oil, and
fennel oil; fatty acids, such as oleic acid and isostearic acid;
ester oils, such as cetyl ethylhexanoate, ethylhexyl palmitate,
octyldodecyl myristate, neopentyl glycol diethylhexanoate, glyceryl
tri-2-ethylhexanoate, octyldodecyl oleate, isopropyl myristate,
glyceryl triisostearate, and glyceryl
monoethylhexanoate-di-para-methoxycinnamate; silicone oils, such as
dimethylpolysiloxane, methyl hydrogen polysiloxane,
methylphenylpolysiloxane, and octamethylcyclotetrasiloxane; and
liquid hydrocarbon oils, such as liquid paraffin, squalene, and
squalane. These liquid oils may be used alone or in combinations of
two or more.
Among these liquid oils, preferred are vegetable oils, ester oils,
and liquid hydrocarbon oils; more preferred are almond oil, olive
oil, soybean oil, octyldodecyl myristate, glyceryl
tri-2-ethylhexanoate, octyldodecyl oleate, isopropyl myristate,
glyceryl triisostearate, and liquid paraffin; and particularly
preferred are isopropyl myristate, olive oil, almond oil, and
soybean oil.
A solid oil is an oil that maintains a solid form at 25.degree. C.
The solid oil to be used in the present invention may be a solid
oil that is generally used in cosmetic preparations,
pharmaceuticals for external use, and the like; examples include
solid oils such as candelilla wax, rice bran wax, beeswax, cotton
wax, carnauba wax, lanolin, shellac wax, ozokerite, ceresin,
polyethylene wax, microcrystalline wax, paraffin, vaseline, lauric
acid, myristic acid, palmitic acid, stearic acid, behenic acid,
12-hydroxystearic acid, undecylenic acid, myristyl myristate, cetyl
myristate, stearyl stearate, cetyl stearate, cetyl palmitate,
cholesteryl stearate, cholesteryl oleate, dextrin palmitate,
stearoyl inulin, hydrogenated jojoba oil, ceresin wax, solid
paraffin wax, polyethylene wax, and silicone wax. These solid oils
may be used alone or in combinations of two or more.
Among these solid oils, preferred are vaseline, paraffin,
cholesteryl stearate, dextrin palmitate, and microcrystalline wax;
and more preferred are vaseline, dextrin palmitate, and
microcrystalline wax.
A higher alcohol is a monohydric alcohol having six or more carbon
atoms in one molecule. While the number of carbon atoms in one
molecule of the higher alcohol to be used in the present invention
may be six or more, it is preferably 6 to 34, and more preferably
14 to 22, for example.
The higher alcohol to be used in the present invention may be a
higher alcohol that is generally used in cosmetic preparations,
pharmaceuticals for external use, and the like; examples include
straight-chain higher alcohols, such as lauryl alcohol, cetyl
alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol,
cetostearyl alcohol, cetanol, and oleyl alcohol; and branched-chain
higher alcohols, such as glycerin monostearyl ether (batyl
alcohol). These higher alcohols may be used alone or in
combinations of two or more.
Among these oily-phase bases, for example, a liquid oil is
preferred.
The content of the oily-phase base in the composition for external
use of the present invention is not particularly limited, and may
be appropriately set, in accordance with the type of the oily-phase
base to be used, the form of the composition for external use, the
use of the composition for external use, and the like; for example,
the content is 50 to 99.9% by weight, preferably 60 to 99.9% by
weight, and more preferably 70 to 99.9% by weight.
Other Components
The composition for external use of the present invention may
optionally contain, in addition to the above-described components,
other bases and additives that are required for, for example,
formulation into a pharmaceutical preparation. These additives are
not particularly limited as long as they are pharmacologically or
cosmetically acceptable; examples include preservatives (such as
methylparaben, propylparaben, benzoic acid, sodium benzoate, and
sorbic acid), fragrances (such as citral, 1,8-cineol, citronellal,
and farnesol), colorants (such as tar dyes (for example, Brown No.
201, Blue No. 201, Yellow No. 4, and Yellow No. 403), cacao color,
chlorophyll, and aluminum oxide), thickening agents (such as
carboxyvinyl polymer, hydroxypropylmethylcellulose, polyvinyl
pyrrolidone, sodium alginate, ethyl cellulose,
carboxymethylcellulose sodium, xanthan gum, and carrageenan), pH
adjusters (such as phosphoric acid, hydrochloric acid, citric acid,
sodium citrate, succinic acid, tartaric acid, sodium hydroxide,
potassium hydroxide, triethanolamine, and triisopropanolamine),
humectants (such as sodium dl-pyrrolidone carboxylate solution,
D-sorbitol solution, and macrogol), stabilizers (such as
dibutylhydroxytoluene, butylated hydroxyanisole, disodium edetate,
sodium metaphosphate, L-arginine, L-aspartic acid, DL-alanine,
glycine, sodium erythorbate, propyl gallate, sodium sulfite, sulfur
dioxide, chlorogenic acid, catechin, and rosemary extract),
polyhydric alcohols (such as glycerin, propylene glycol,
dipropylene glycol, butylene glycol, and polyethylene glycol),
antioxidants, ultraviolet absorbers, chelating agents, binders,
buffers, solubilizing agents, and antiseptics.
Emulsification Type, Product Forms, and Use
The composition for external use of the present invention is in the
form of a dispersion of the water-soluble fraction in the oily
phase, and thus, is a water-in-oil-type (W/O-type) emulsion.
Because the composition for external use of the present invention
is of the water-in-oil type, the percutaneous absorption properties
of the composition for external use containing the water-soluble
substance can be effectively improved. The composition for external
use of the present invention may also be formulated into a
W/O/W-type pharmaceutical preparation, by further dispersing the
composition in the aqueous phase in accordance with a conventional
method.
The composition for external use of the present invention can be
used as an agent for external use such as, for example, a cosmetic
preparation or a pharmaceutical for external use. While the product
form of the composition for external use of the present invention
is not particularly limited, examples include creams, ointments,
emulsions, gels, oils, lotions, liniments, and aerosols. Among the
above, for example, creams, ointments, emulsions, oils, and lotions
are preferred.
The use of the composition for external use of the present
invention can be appropriately designed, in accordance with the
component as the water-soluble substance to be encapsulated.
Furthermore, the composition for external use of the present
invention can be used as a drug carrier, because it has excellent
percutaneous absorption properties, and a water-soluble substance
having a relatively high molecular weight can be encapsulated
therein.
Production Method
The composition for external use of the present invention can be
produced in accordance with a known technique for formulating
compositions for external use. Examples of the method for producing
the composition for external use of the present invention include a
method in which the components to be incorporated are divided into
water-soluble components and oily components, an aqueous phase
containing the water-soluble components and an oily phase
containing the oily components are prepared, and these phases are
emulsified in accordance with a known technique. Specifically, the
composition for external use of the present invention can be
produced by preparing the aqueous phase in which the water-soluble
substance is dissolved in water, preparing the oily phase
containing the surfactant and the oily-phase base, and mixing and
emulsifying the prepared aqueous phase and oily phase.
EXAMPLES
The present invention will be described next in more detail with
reference to examples, although the invention is in no way limited
thereto.
Experimental Example 1
<Preparation of Compositions for External Use>
A heparinoid was weighed into a tube to give the formulation shown
in each of Tables 2 to 6, purified water was added thereto, and the
heparinoid was dissolved using a vortexer to prepare an aqueous
solution of the heparinoid. Next, an oily-phase base was weighed
into a beaker to give the amount shown in each of Tables 2 to 6,
and heated in a hot water bath (80.degree. C.) for 5 minutes or
longer, under stirring with a stirrer. Into the beaker, a
surfactant dissolved in advance by heating in a hot water bath
(70.degree. C.) was added in the amount shown in each of Tables 2
to 6, and heated in a hot water bath (80.degree. C.) for 10 minutes
or longer, under stirring with a stirrer. Then, the beaker was
removed from the hot water bath, and 1 ml of the aqueous solution
of the heparinoid prepared above was slowly added dropwise, under
stirring, into the beaker. This mixture was stirred until it was
cooled to room temperature, thereby obtaining a composition for
external use containing a water-soluble substance in the form of a
water-in-oil-type emulsion.
<Evaluation of Percutaneous Absorption Properties>
(Percutaneous Absorption Test)
A percutaneous absorption test was performed using a Franz cell, in
accordance with the following procedure: A vertical Franz cell
(model: TP-8S, manufactured by VIDREX) was fixed on a stirrer, and
connected to a water bath and kept at about 32.degree. C. Skin
(diameter: about 1.5 cm) excised from a hairless mouse (Hos: HR-1)
was placed in the Franz cell with the horny layer facing upward.
The cap of the Franz cell was placed thereon and fixed with a
clamp. Next, the receptor was filled with phosphate buffer (PBS),
while avoiding the entry of air. Then, 1 ml (1 g) of each of the
compositions for external use obtained above was applied to the
donor (1.77 cm.sup.2). After a lapse of a sampling time, 300 .mu.l
of the receptor solution was collected, and fresh PBS was supplied
instead. The above procedure was repeated, and the test was
performed until an end time (24 hours).
(Measurement of the Amount of Percutaneous Absorption (Amount of
Permeation of Heparinoid)
The amount of the heparinoid percutaneously absorbed was determined
by the colorimetric method described below, using the measurement
kit "Test Team Heparin S" (manufactured by Sekisui Medical Co.,
Ltd.).
(1) Preparation of Reagents
Using the above-mentioned measurement kit, reagents were prepared
as shown in Table 1 below.
TABLE-US-00001 TABLE 1 Antithrombin 10 ml of distilled water was
added to the vial, III solution and the contents were dissolved.
Factor Xa 10 ml of distilled water was added to the vial, solution
and the contents were dissolved. Substrate 20 ml of distilled water
was added to the vial, solution and the contents were dissolved.
Quenching 20 ml of distilled water was added to 20 ml of solution
acetic acid and mixed.
(2) Preparation of Standard Solutions
Using Test Team Heparin S (manufactured by Sekisui Medical Co.,
Ltd.), and PBS as a solvent, standard solutions for the calibration
curves at eight points, i.e., 0, 0.03, 0.1, 0.3, 1, 3, 10, and 30
.mu.g/mL, were prepared.
(3) Measurement Method
To each well of a 96-well plate warmed to 37.degree. C., 5 .mu.l of
the antithrombin III solution was added, and then 45 .mu.l of each
of the standard solutions or the sample (receptor solution) was
added. The plate was sealed, and mixed on a plate shaker for 10
seconds and then warmed at 37.degree. C. for about 2 to 6 minutes.
Then, 25 .mu.l of the Factor Xa solution was added to each well,
and the plate was mixed again on the plate shaker for 10 seconds
and warmed at 37.degree. C. for about 30 seconds. Then, 50 .mu.l of
the substrate solution was added to each well, and the plate was
mixed again on the plate shaker for 10 seconds and warmed at
37.degree. C. for 3 minutes. After 3 minutes of warming, 75 .mu.l
of the quenching solution was added to each well, and the plate was
mixed on the plate shaker for 10 seconds. Thereafter, absorbance at
405 nm was read by a plate reader (GENios manufactured by TECAN),
and the heparinoid concentration was determined based on the
calibration curves. The percutaneous absorption properties were
evaluated as follows: "x": The amount of permeation of the
heparinoid after 24 hours was 0 .mu.g. "A": The amount of
permeation of the heparinoid after 24 hours was more than 0 to 1.26
.mu.g. "O": The amount of permeation of the heparinoid after 24
hours was more than 1.26 to 2.52 .mu.g. "0": The amount of
permeation of the heparinoid after 24 hours was more than 2.52
.mu.g.
TABLE-US-00002 TABLE 2 Examples 1 2 3 4 5 6 7 8 9 10 11 12 13
Oily-Phase Isopropyl 96.2 95.95 95.2 94.7 92.7 96.7 95.7 94.7 94.2
91.2 --- -- -- Base Myristate Squalane -- -- -- -- -- -- -- -- --
-- 94.2 -- -- Light Liquid -- -- -- -- -- -- -- -- -- -- -- 94.2 --
Paraffin Liquid Paraffin -- -- -- -- -- -- -- -- -- -- -- -- --
Almond Oil -- -- -- -- -- -- -- -- -- -- -- -- 94.2 Olive Oil -- --
-- -- -- -- -- -- -- -- -- -- -- Soybean Oil -- -- -- -- -- -- --
-- -- -- -- -- -- Surfactant Glyceryl 3 3 3 3 6 2 3 4 4.5 7.5 4.5
4.5 4.5 Monooleate Aqueous-Phase Water 0.5 0.75 1.5 2 1 1 1 1 1 1 1
1 1 Base Water-Soluble Heparinoid 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3
0.3 0.3 0.3 0.3 0- .3 Substance Total (Weight %) 100 100 100 100
100 100 100 100 100 100 100 100 100 Percutaneous Amount of 4.06
7.97 3.01 4.01 12.9 8.9 11.5 11.9 32.84 5.32 1.3 2.12 20.67
Absorption Permeation (.mu.g) after 24 Hours Properties Evaluation
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Percutaneous Absorption Properties
TABLE-US-00003 TABLE 3 Examples 14 15 16 17 18 19 20 21 Oily-Phase
Isopropyl Myristate -- -- 40 43 43 43 43 43 Base Squalane -- -- --
-- -- -- -- -- Light Liquid Paraffin -- -- -- -- -- -- -- -- Liquid
Paraffin -- -- 54.2 -- 5 10 2 -- Almond Oil -- -- -- 51.2 46.2 41.2
49.2 52.7 Olive Oil 94.2 -- -- -- -- -- -- -- Soybean Oil -- 94.2
-- -- -- -- -- -- Surfactant Glyceryl Monooleate 4.5 4.5 4.5 4.5
4.5 4.5 4.5 3 Aqueous-Phase Water 1 1 1 1 1 1 1 1 Base
Water-Soluble Heparinoid 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Substance
Total (Weight %) 100 100 100 100 100 100 100 100 Percutaneous
Amount of Permeation 9.6 18.81 4.97 2.12 1.96 3.97 3.01 4.21
Absorption (.mu.g) after 24 Hours Properties Evaluation of
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Percutaneous Absorption Properties
TABLE-US-00004 TABLE 4 Examples 22 23 24 25 26 27 28 29 30 31
Oily-Phase Isopropyl Myristate 94.2 94.2 95.7 94.2 95.7 94.2 94.2
95.7 94.2 94.2 Base Surfactant Sucrose Erucate 4.5 -- -- -- -- --
-- -- -- -- Polyoxyethylene -- 4.5 -- -- -- -- -- -- -- --
Hydrogenated Castor Oil 60 Diglyceryl Monooleate -- -- 3 4.5 -- --
-- -- -- -- Tetraglyceryl Monooleate -- -- -- -- 3 4.5 -- -- -- --
Decaglyceryl Monooleate -- -- -- -- -- -- 4.5 -- -- -- Decaglyceryl
Trioleate -- -- -- -- -- -- -- 3 4.5 -- Sorbitan Monooleate -- --
-- -- -- -- -- -- -- 4.5 Aqueous- Water 1 1 1 1 1 1 1 1 1 1 Phase
Base Water- Heparinoid 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Soluble Substance Total (Weight %) 100 100 100 100 100 100 100 100
100 100 Percutaneous Amount of Permeation 3.29 2.34 2.86 3.55 21.43
5.05 35.31 22.03 3.49 5.51 Absorption (.mu.g) after 24 Hours
Properties Evaluation of Percutaneous .circleincircle.
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TABLE-US-00005 TABLE 5 Examples 32 33 34 35 36 37 38 39 40 41
Oily-Phase Isopropyl Myristate 94.2 94.2 94.2 94.2 94.2 94.2 94.2
94.2 94.2 92.7 Base Surfactant Sorbitan Trioleate 4.5 -- -- -- --
-- -- -- -- -- Glyceryl Monostearate -- 4.5 -- -- -- -- -- -- -- --
Diglyceryl Monostearate -- -- 4.5 -- -- -- -- -- -- -- Glyceryl
Distearate -- -- -- 4.5 -- -- -- -- -- -- Sorbitan Monostearate --
-- -- -- 4.5 -- -- -- -- -- Glyceryl Monomyristate -- -- -- -- --
4.5 -- -- -- -- Decaglyceryl -- -- -- -- -- -- 4.5 -- -- --
Monopalmitate Sorbitan Monopalmitate -- -- -- -- -- -- -- 4.5 -- --
Sorbitan Monolaurate -- -- -- -- -- -- -- -- 4.5 -- Glyceryl
Monooleate -- -- -- -- -- -- -- -- -- 4.5 Aqueous- Water 1 1 1 1 1
1 1 1 1 2.5 Phase Base Water- Heparinoid 0.3 0.3 0.3 0.3 0.3 0.3
0.3 0.3 0.3 0.3 Soluble Substance Total (Weight %) 100 100 100 100
100 100 100 100 100 100 Percutaneous Amount of Permeation (.mu.g)
8.66 3.57 4.05 3.81 3.51 3.00 24.25 2.95 5.63 4.78 Absorption after
24 Hours Properties Evaluation of Percutaneous .circleincircle.
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TABLE-US-00006 TABLE 6 Comparative Examples 1 2 3 4 Oily-Phase
Isopropyl 93.7 72.5 99.7 -- Base Myristate Squalane -- -- -- --
Light Liquid -- -- -- -- Paraffin Liquid -- -- -- -- Paraffin
Almond Oil -- -- -- 99.7 Olive Oil -- -- -- -- Soybean Oil -- -- --
-- Surfactant Glyceryl -- -- -- -- Monooleate Polyoxyethylene 3 20
-- -- Hydrogenated Castor Oil 10 Aqueous-Phase Water 3 7 -- -- Base
Water-Soluble Heparinoid 0.3 0.5 0.3 0.3 Substance Total (Weight %)
100 100 100 100 Percutaneous Amount of 0 0 1.26 0.70 Absorption
Permeation (.mu.g) Properties after 24 Hours Evaluation of X X
.DELTA. .DELTA. Percutaneous Absorption Properties Notes Properties
of Dis- Dis- Undis- Undis- Water-Soluble solved solved solved
solved Substance
The results are shown in Tables 2 to 6. As is evident from Tables 2
to 6, the compositions for external use of the present invention,
wherein the water-soluble fraction containing the solution in which
the water-soluble substance is dissolved in water is dispersed in
the oily phase, were confirmed to have excellent percutaneous
absorption properties.
Experimental Example 2
<Preparation of Compositions for External Use>
Water-in-oil-type compositions for external use were obtained as in
Experimental Example 1, except that the components were weighed to
give the formulations shown in Table 7, and fluorescein (uranine)
was used instead of the heparinoid.
<Evaluation of Percutaneous Absorption Properties>
A percutaneous absorption test was performed on each of the
obtained compositions for external use, using the same method as
that of Experimental Example 1. An aqueous solution of uranine (1
mg/ml) was serially diluted (0.0001024 to 200 .mu.g/ml) to prepare
standard solutions for the calibration curves. Then, 200 .mu.l of
the sample obtained by the percutaneous absorption test or each of
the standard solutions was added to each well of a 96-well plate.
Then, the emission intensity at 535 nm was read by a plate reader
(GENios manufactured by TECAN) at an excitation wavelength of 492
nm, and the amount of percutaneous permeation of uranine was
determined from the reading. Furthermore, the amount of intradermal
retention (.mu.g) of uranine at 24 hours was similarly determined
using an extract obtained by cryogenically grinding the skin after
the test, and extracting it with 1 ml of purified water.
TABLE-US-00007 TABLE 7 Comparative Example Example 5 42 Oily-Phase
Base Light Liquid -- 95.9 Paraffin Surfactant Glyceryl -- 3
Monooleate Aqueous-Phase Base Water 99.9 1 Water-Soluble
Fluorescein 0.1 0.1 Substance (Uranine) Total (Weight %) 100 100
Percutaneous Amount of Permeation 0 0 Absorption (.mu.g) at 2 Hours
Properties Amount of Permeation 0 36.56 (.mu.g) at 6 Hours Amount
of Permeation 51.57 215.47 (.mu.g) at 24 Hours Amount of
Intradermal 1.74 3.48 Retention (.mu.g) at 24 Hours
The results are shown in Table 7. As is evident from Table 7, the
composition for external use of the present invention was confirmed
to have excellent percutaneous absorption properties even when it
contains uranine as the water-soluble substance.
Experimental Example 3
<Preparation of Compositions for External Use>
Water-in-oil-type compositions for external use were obtained as in
Experimental Example 1, except that the components were weighed to
give the formulations shown in Table 8, and
fluoresceinamine-labeled sodium hyaluronate (manufactured by PG
Research, product code: FAHA-U2, molecular weight: 5,400 daltons)
was used instead of the heparinoid.
<Evaluation of Percutaneous Absorption Properties>
A percutaneous absorption test was performed on each of the
obtained compositions for external use, using the same method as
that of Experimental Example 1. The standard substance of
fluoresceinamine-labeled sodium hyaluronate was serially diluted
(0.025 to 100 .mu.g/ml) to prepare standard solutions for the
calibration curves. Then, 100 .mu.l of the sample obtained by the
percutaneous absorption test or each of the standard solutions was
added to each well of a 96-well plate. Then, the emission intensity
at 518 nm was read by the Ensight multimode plate reader
(manufactured by PerkinElmer Japan) at an excitation wavelength of
492 nm, and the amount of percutaneous permeation of
fluoresceinamine-labeled sodium hyaluronate was determined from the
reading.
TABLE-US-00008 TABLE 8 Compa- Compa- Compa- rative rative rative
Exam- Exam- Exam- Exam- ple 43 ple 6 ple 7 ple 8 Oily-Phase
Isopropyl 94.49 98.99 -- -- Base Myristate Surfactant Glyceryl 4.5
-- -- -- Monooleate Aqueous-Phase Water 1 1 99.99 -- Base PBS -- --
-- 100 Water-Soluble Fluorescein- 0.01 0.01 0.01 -- Substance
amine-Labeled Sodium Hyaluronate Total (Weight %) 100 100 100 100
Percutaneous Amount of 5.23 1.68 0.38 0.02 Absorption Permeation
(.mu.g) Properties at 24 Hours
The results are shown in Table 8. As is evident from Table 8, the
composition for external use of the present invention was confirmed
to have excellent percutaneous absorption properties even when it
contains sodium hyaluronate as the water-soluble substance.
Experimental Example 4
<Preparation of Compositions for External Use>
Water-in-oil-type compositions for external use were obtained as in
Experimental Example 1, except that the components were weighed to
give the formulations shown in Table 9, and FITC-labeled ovalbumin
was used instead of the heparinoid.
FITC-labeled ovalbumin was prepared in accordance with the
following procedure: 30 mg of ovalbumin was dissolved in 2 ml of a
carbonate buffer at pH 9.3 to prepare an ovalbumin solution.
Separately, 2.6 mg of FITC was dissolved in 20 .mu.l of
dimethylsulfoxide to prepare a FITC solution. The ovalbumin
solution and the FITC solution were mixed, and then the mixture was
allowed to stand at room temperature for 12 hours and reacted.
Next, the reaction mixture was applied to gel chromatography (PD10
column manufactured by GE Healthcare Japan), and the eluted orange
liquid was collected. This liquid was freeze-dried to obtain
FITC-labeled ovalbumin.
<Evaluation of Percutaneous Absorption Properties>
A percutaneous absorption test was performed using a Franz cell, in
accordance with the following procedure: A vertical Franz cell
(model: TP-8S, manufactured by VIDREX) was fixed on a stirrer, and
connected to a water bath and kept at about 32.degree. C. Skin
(about 1.5-cm square) excised from a pig (Yucatan micro pig) was
placed in the Franz cell with the horny layer facing upward. The
cap of the Franz cell was placed thereon and fixed with a clamp.
Next, the receptor was filled with phosphate buffer (PBS), while
avoiding the entry of air. Then, 200 .mu.l of each of the
compositions for external use obtained above was applied to the
donor (1.77 cm.sup.2).
After 24 hours from the application, the skin was removed from the
Franz cell, and the skin surface was washed with a 20% aqueous
solution of ethanol. Then, the skin was cut into small pieces, and
extraction was performed by immersing the skin in 500 .mu.l of an
extraction solvent (PBS:acetonitrile:methanol=2:1:1) for 24 hours.
The extract was then filtered through a 0.20-.mu.m filter
(Advantec, 13HP020AN) to obtain a skin extract.
Using the extraction solvent, the standard substance of
FITC-labeled ovalbumin was serially diluted (0.016 to 10 .mu.g/ml)
to prepare standard solutions for the calibration curves. Using a
fluorometer (PerkinElmer, LS-55), fluorescence intensities
(wavelength: 522.5 nm) of FITC were measured for the skin extract
and the standard solutions prepared above, and the amount of
FITC-labeled ovalbumin permeated into the skin (amount of
intradermal retention at 24 hours) was quantified.
TABLE-US-00009 TABLE 9 Example Comparative 44 Example 9 Oily-Phase
Isopropyl Myristate 95.4 -- Base Surfactant Glyceryl Monooleate 4
-- Aqueous-Phase Water 0.5 -- Base PBS -- 99.9 Water-Soluble
FITC-Labeled 0.1 0.1 Substance Ovalbumin Total (Weight %) 100 100
Percutaneous Amount of Permeation 5.91 0.04 Absorption (.mu.g) at
24 Hours Properties
The results are shown in Table 9. As is evident from Table 9, the
composition for external use of the present invention was confirmed
to have excellent percutaneous absorption properties even when it
contains ovalbumin as the water-soluble substance.
* * * * *
References